This 20W amplifier was found in 283 circuits from the 90s. The MOSFET admits equivalents. The power supply must be dual, and the transistors must be mounted on good heat sinks.
This circuit with JFET and Unijunction was found in an ancient American documentation. The...
This metering bridge circuit uses one power supply only. The operational ones depend on the...
We found this configuration in the 1964 RCA transistors manual. As indicator loads in each stage,...